<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        a:link  /*表面*/
        {
            color: black;
        }
        a:hover /*悬浮*/
        {
            color: red;
        }
        a:active /*按住*/
        {
            color: green;
        }
        a:visited /*已经访问 */
        {
            color: purple;
        }
        input:link   /*表面*/
        {
            color: blue;
        }
        input:hover /*悬浮*/
        {
            color: red;
        }
        input:active /*按住*/
        {
            color: green;
        }
    </style>
</head>
<body>
    <h1>伪类选择器</h1>
    <a href = "#">不跳转</a>
    <br>
    <input type = "button" value = "按钮">
</body>
</html>